There are various vehicles which are used to carry loads, one of which is the dump truck. A dump truck normally carries particulate material such as gravel, soil or grain. The vehicle has a dump body which involves a generally rectangular box pivotally connected to the vehicle chassis or frame. Means, such as hydraulic cylinder and piston units, are provided to raise the forward end of the box so that the contents thereof will slide to the rear to exit the box through the tailgate. The tailgate extends across the box and is typically hinged to the box along an axis that extends along the top edge of the tailgate. The tailgate can be locked to the box to prevent inadvertent opening and it can also include a smaller opening with its own manually openable gate to direct the contents of the box in a path narrower than the full width of the tailgate. The smaller opening is used when it is desired to feed the box contents to a chute or a conveyor for movement along a particular path. A dump box can be provided on a self-propelled vehicle, creating a dump truck, or it can be provided on a towed vehicle such as a trailer or a rail car.
One particular task commonly performed is the carrying of crushed stone or gravel to a construction site. When residential housing is being constructed it is normal to provide a base of gravel within the boundaries of the foundation before the basement floor is poured. In a multi-unit housing tract there are many foundations under construction at the same time and very often a dump truck is unable to back right up to the foundation to deposit its load within the foundation. Furthermore, gravel is normally placed adjacent the outer wall of the foundation over and around the weeping tile of the ground water collection system. Again, the dump truck is often prevented from dumping its load exactly where it is needed. In such circumstances a "stone slinger" truck is used to deliver the gravel to the dump site.
A stone slinger has a hopper-like body that carries the gravel and includes a conveyor therebelow that receives the gravel from the hopper body at a position remote from the dump site and conveys it to the dump site itself within or adjacent the foundations walls. It can be moved as desired to place gravel at different spots so that the gravel can be spread more evenly by a gang of workmen. This way of distributing gravel at the construction site is quite inefficient since workmen must monitor the stone slinger, moving the vehicle as desired relative to the foundation. The workmen must also spread the gravel after it has been dumped and they must also move the stone slinger from one foundation to another after dumping is complete. A stone slinger vehicle is very specialized and very expensive to own, operate or rent.